It is known to use a hybrid combination of an internal combustion engine and an electric motor to power a vehicle. For electric motor rotors designed such that an inner diameter of the rotor is a “clearance fit” (also known as a “sliding fit” or “slip fit”) about an outer diameter of a hub, a means of axially retaining the rotor on the hub is required. Typically, one side of the hub will have a formed-in flange providing axial retention for that side of the hub. However, the other side of the hub needs a means, which does not interfere with assembling the rotor and the hub, of axially retaining the rotor after the assembly of the rotor and the hub.
It is known to secure the rotor to the hub via a formed-in flange on the hub and a nut threaded onto the hub after installation of the rotor. The threading operation and use of a nut increases the cost, complexity, and parts count of the resulting assembly. It also is known to secure the rotor to the hub via a formed-in flange on the hub and, after installing the rotor on the hub, bending a portion of the hub to form one or more tab to axially retain the rotor. The tabs do not provide adequate axial retention for rotors having larger masses. It also is known to fix a resolver rotor to the hub using the above methods.